1. Field of the Invention
The present invention relates to a contact for use in an electrical connector, and particularly to a contact used in an electrical connector for electrically connecting a mother board and a daughter board together, wherein the daughter board is oriented perpendicularly to the mother board.
2. Description of Related Art
Backplane/mother board is a printed circuit board on the upper side of which a plurality of daughter boards are perpendicularly mounted to the mother board for easy removal. One way of electrically connecting the daughter board to the mother board, a backplane connector is attached on the mother board, and a mating connector is attached on the daughter board, whereby both connectors consist of an electrical connector assembly. When the two connectors are joined, a plurality of first contacts directed upwardly between the backplane connector are connected to a plurality of corresponding second contacts directed downwardly between the mating connector. However, regarding to high density array of the first and second contacts, straightly mating is able to damage connection between the first and second contacts. For connecting a mother board and a daughter board in a mutually perpendicular relationship in high density, referring to U.S. Pat. No. 5,975,921, an electrical connector which has inner circuit board is applicable to a plug or receptacle, although generally applied as a receptacle to mount on a mother board. The connector has a plurality of contacts each having a solder tail or surface mount lead for soldering to the mother board, a contact retention portion and a contact portion engaging with a pad of the inner circuit board. The inner circuit board is inserted into the connector whereby the contact portions are laterally deflected to generate a reaction force large enough to ensure a reliable engagement between the contact portions and the pads of the inner circuit board. However, the pressing force of the inner circuit board on the contact portion generates a moment which can adversely affect the solder connection between the solder tails or surface mount leads of the contacts and the mother board.
To solve this problem, prior art proposed that the contacts each have an enlarged retention portion between the contact portion and the soldering tail for engaging with a housing of the connector. The enlarged retention portion unavoidably increases the size of the contact, which is unfavorable regarding the minimization trend of connectors.
Hence, there is a need to have an improved contact which can solve the problem of the prior art.
Accordingly, it is an object of the present invention to provide a contact used in an electrical connector, which is capable of improving the engagement between the electrical connector and a printed circuit board.
It is another object of the present invention to ensure each contact has reliable contact with a circuit trace of a printed circuit board to establish an efficient electrical connection.
According to one aspect of the present invention, a contact is used in an electrical connector for connecting first and second printed circuit boards in a mutually perpendicular relation. The contact comprises a body portion having a first side and a second side opposite to the first side, and an upper arm and a lower arm. The upper arm extends upwardly from the body portion. The lower arm extends downwardly from the body portion and sideways in a direction from the first side toward the second side of the body portion. The upper arm has a free end with a curved edge adapted for engaging with the first printed circuit board. The curved edge faces in a direction from the second side toward the first side of the body portion. The lower arm has a free end adapted for engaging with the second printed board and a curved portion connecting with the body portion.
According to another aspect of the present invention, the curved portion extends from the body portion. The body portion forms a plurality of serrations at the first side adapted for engaging with a housing of the electrical connector.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.